Radiobiological EffectsThe Biological Effect of Ionizing Radiation on Living Organisms
When cells are exposed to radiation it causes a change in the DNA of the cell. The radiation damage to the cell and tissue of the human body are call Radiobiologial Effect
When DNA is damaged by radiation, its coded language is also damaged resulting in cell death.
Direct Cell death may take up to days or months
Cumulative expression of carcinogenesis may take years or generations
Radiobiological Effects: DeterministicDeterministic effects only occur once a threshold of exposure has been exceeded.
Dependent on amount of dose
Threshold level is known ie; cataracts, erythema, skin cancers, leukemia
Appropriate radiation protection methods and occupational dose limits prevent the likelihood of these effects occurring.
Extremely rare: ie; erythema, sterility, radiation sickness
Radiobiological Effects: StochasticCurrent thinking is that Stochastic Effects occur following a linear no-threshold hypothesis
No threshold for these effects, with risk occurring as dose increases ie; cancer, hereditary defects in later generations
Stochastic effects are cumulative
Occupational monitors measured in effective and cumulative dose
However, dose is negligible and impact is unknown when environmental exposure is taken into account.
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